Here is a post from Tracey Seddon, Head of Organics Conservation:
"I was relieved last week to get the fabulous Amber Cabinet back on display where it belongs in the Walker Art Gallery. I had reluctantly and rather hastily taken the decision to remove it from display back in 2011 when rumblings caused by the demolition of the Central Library next door had lead to some small fragments falling off. I was very concerned about the prospect of more damage.
This is possibly the most fragile object in National Museums Liverpool's collections. It is vulnerable to fragmentation whenever it is handled, moved or exposed to different environmental conditions. It is nerve-wracking to have it out of its sealed, environmentally stable showcase. So what makes it so fragile? Well, amber is an organic material, an ancient tree resin, which starts to degrade and become more brittle as soon as it is mined and exposed to oxygen and temperature changes. Also, it contains lots of very fine natural fissures and air bubbles which create weaknesses. Amber will eventually crumble to dust. In this case, my job is to stop it, or at least slow down the process.
The fragmentation can be difficult to see until actual breakage starts to happen but in the macroscopic image here I think the problem is all too clear. The area of amber shown is in reality about 14mm x 14mm. To the naked eye it simply has a dull surface appearance. Viewed at x20 magnification you can clearly see the extent of the crizzling.
This is part of a carved roundel on the right side of the cabinet which had developed a severe crack and was found to be entirely fragmenting from the back. It needed to be removed from the cabinet to repair the damage before replacing it securely.
Incidentally, the clarity of the image here is unusual. Photomicrographs of three-dimensional objects are typically only partly in focus with other areas closer to or further from the lens out of focus. This image was made with the use of very new technology which takes microscopic images in several planes and from several angles simultaneously, and then digitally knits them together to give an image which is in focus on every surface. Magic."